Venetian blind cord-controlling organization



Feb. 27, 1940. s. R. BOND ET AL 2,192,002

VENETIAN BLIND CORD-CONTROLLING ORGANIZATION Filed Dec. 12, 1936 INVENTORS 13/, p 13.502252 and BY flaw! fiorfwtzwz,

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2950/ ATTORNEYS Patented Feb. 27, 1940 PATENT OFFICE VENETIAN BLIND CORD-CONTROLLING ORGANIZATION Scott R. Bond, New York, N. Y., and Hans K. Lorentzen, Montclair, N. J said Bond assign'or to said Lorentzen Application December 12, 1936, Serial No. 115,486

2 Claims.

This invention relates to Venetian blinds, and particularly to an organization for controlling the cords used for raising and lowering the blind.

Various locks have heretofore been proposed 5 for locking the raising and lowering cords of a Venetian blind, and some of such locks operate quite well. However, it is desirable to increase the ease and convenience with which the cords may be manipulated, increase the positiveness of the lock, and diminish the care which is required in handling the cords during looking or unlocking.

An object of the present invention is to provide a Venetian blind cord-controlling organization which facilitates manipulation of the lift cords in raising and lowering the blind.

Another object of the invention is to provide a cord lock which may be easily and conveniently operated, and is positive in holding.

A further object of the invention is to provide a cord lock which readily and firmly holds the cords without chewing or damaging the cords.

Various specific and detailed objects of the invention will be apparent to those skilled in the art from the following disclosure of two illustrative embodiments of the invention.

Fig. I of the drawing is a vertical cross section through the suspension bar of a Venetian blind embodying the present invention. The section is taken approximately on the line II of Fig. II.

Fig. II is a longitudinal section through the suspension bar, taken in general. on the line 11-11 of Fig. I.

Fig. HI is a cross section in a vertical plane, taken approximately on the line III1II of the Fig. II. This view shows the locking dog in cordrelease position. i

Fig. IV is a detail sectional view showing the cord lock as in Fig. II, but with the dog in cord locking position.

Fig. V is an isometric view of the corrugated pulley shown in Figs. II, IV, VI and VII.

Fig. VI is a plan view of a cord lock casing having a modified locking structure incorporated therein.

Fig. VII is a longitudinal section through the modified cord lock, taken in general on the line VII-VII of Fig. VI.

- .Fig. VIII is a detail view, partially in section, showing a modified pulley.

A suspension bar I is provided on its top surface with a longitudinal channel 2; and adjacent to the right hand end of the bar there is an inclined passage 3, which leads from the channel tilting slats, and that the other slats of 2 to the bottom of the bar. It will be understood that as usual the suspension bar I is mounted on brackets at the top of a window frame, and that the conventional assembly of tilting slats is suspended from the suspension bar I. Operating cords 4 and 5 for raising the blind pass upwardly through holes in the suspension bar to the-channel 2, over pulleys such as pulley 5, and thence longitudinally in channel 2 to the right hand end of the bar where 10 they pass downwardly through cord-controlling mechanism.

A stamped sheet metal bracket 1! is-screwed or otherwise secured to the under-surfaces of the suspension bar I, adjacent to inclined passage 3. 15 This bracket has a depending leg l which is slotted at 7 to receive the pintle 3 which is attached to one end of the tilt slat 9. It will be understood, of course, that the tilt slat 9 is the uppermost slat'in the conventional assembly. of 20 the blind are supported from and articulated with the tilt slat 9. Pivoted to the bracket leg I is a retainer lever iii which detachably secures the pintle 8 in slot l Retainer lever I!) has a nose 25 Ill which, in the position shown in the drawing, projects across slot l and holds the pintle 8 in place; and the retainer also-has a finger IIl which is adapted to engage the upper edge of slot I to prevent accidental movement or the retainer I 0 to a position permitting removal of the pintle 8. However, when it is desired to remove the pintle, retainer lever I0 can be flexed to the right sufiiciently to permit finger Ifl to move alongside of bracket leg I so that the 35 pintle may be removed from the slot.

Positioned in inclined passage 3 is a frame formed as an inclined hollow cord lockcasing II, which is conveniently made of sheet metal and attached to the bracket 1. If desired the 40 hollow casing Il may be stamped integral with the bracket I. At one side of the hollow casing II a corrugated pulley I2 is rotatably mounted on an axis extending transversely of the casing.

At the other side of the casing there is a pivotally 45 mounted rubber locking dog I3 having a nose portion l3 which faces the pulley I2. The casing II includes a rigid flange II which extends over the locking dog I3, and which will be referred to later. 50

The two lift cords 4 and 5 pass side-by-side over the pulley I2 and downwardly between the pulley. and the locking dog I3. As will be seen from the Fig. I the inclination of the casing II is such that the line of the axis of the casing passes in front of the tilt slat 9. Thus, the lift cords extend in a straight line from the casing Ii to a point in front of the tilt slat 9; so that the cords are readily manipulated without any catching of the cords on the end of the tilt slat. Suitable means may be used to keep the cords in parallelism and prevent twisting of the cords in or near the casing H. The means shown is a spring wire M which passes between cords 4 and 5, and which has a bent end l4 that is hooked through a hole in bracket leg 1. The

other end of the wire has a looped end I l which is screwed to the suspension bar i.

When it is desired to ehange the elevation of the blind, the operator inclines the lift cords slightly toward the pulley l2 and pulls the cords (or pays them out) until the blind is brought to the desired elevation. Then the cords 4 and 5 are inclined slightly toward the locking dog l3, whereupon the cords engage nose I3 and slight upward movement of the cordselevates the locking dog to the locking position shown in Fig. IV. The pulley l2 constitutes an abutment against which the cords are. locked, and the dog l3 distorts and wedges the cords tightly against the pulley. As the pulley rotates with the dog moving to locked position, the apices of the pulley corrugations act as high-spots, so that the dog is free to advance an additional increment as a high-spot passes The next corrugation or highspot greatly increases the clamping pressure and prevents any slipping of the cords. To release the lock cords it is only necessary to pull downwardly on the cords 4 and 5 which depend from the cord lock.

While we prefer to use a corrugated pulley as shown at l2, we have found that satisfactory results can also be obtained with a plain pulley or roller, i. e. one having a smooth cord engaging face. To obtain the greatest increase of clamping pressure with a corrugated roller, the corrugations should be relatively coarse as shown; and the apices of the corrugations may be spaced apart by a distance approximately equal to the diameter of the cord. Since the dog l3 distorts and yields as it wedges the cords, firm clamping of both cords is assured despite small variations in the size of the two cords 4 and 5.

Under some conditions dog i3 in looking the cords will move to a position higher than that shown in Fig. IV. This may be brought about in several ways, e. g. the cords 4 and 5 may be under-size, the load on the cords may be very heavy, or the dog may be made of very soft rubber to improve the sensitiveness and holding of the look. In such case the dog moves against flange I I in the final phases of its distortion, the flanges supporting the dog and preventing it from being crowded above the pulley ll. Of course, the dog is also supported laterally by the sides of the casing H, which are close against the dog, but do not bind it.

In the modification shown in Fig. VI and VII a small rubber dog I5 is held by a pin IS in a U-shaped swinging frame II. This frame has side arms i1 and l1" and is pivoted at [8 to a frame formed as a hollow casing l9, which coraioaoos responds to casing ll inthe first form of the invention. The cords pass between pulley i2 and the dog 15 and the operation is similar to the first form of the invention. Preferably, the frame is provided with a projection H which supports the rubber dog during distortion, similarly to the support furnished by project II in the first form of the invention. The sides of the dog are of course, supported by the two sides I'l and ll of the swinging frame. It will be understood that in use the casing I8 is preferably attached to a bracket 1 in the same manner as the casing H in the first form of the invention. If desired the casing l9 may be stamped integrally with a bracket such as bracket I.

In Fig. VIII there is shown a modified pulley H2, which difiers from pulley I2 only in that its surface is grooved in axial section, instead of being straight in axial section. This circumferential grooving of the pulley causes it to crowd the cords 4 and 5 together when they are clamped. Additionally, the rubber locking dog has a grooved cord-clamping face, as the dog D in Fig. VIII. In such case the dog also tends to crowd the two cords together. In Figs. I to VII the locking dogs are shown with cord-clamping faces which are rectilinear in section perpendicular to the cords, but, it will be understood that the dogs of Figs. I to VII may also be made with cordclamping faces grooved like dog D in Fig. VIII. It will also be understood that either a plain faced dog or a grooved faced dog may be used with any of the types of pulleys, viz. pulley I2,

pulley H2, or a non-corrugated pulley having either a plain or a grooved face.

In compliance with the patent statutes we have disclosed the best forms in which we have contemplated applying our invention, but it will be understood that the forms disclosed are illustrative of the invention, and that the scope of the invention is defined by the claims which follow herein.

We cla m:

l. A cord lock comprising: a pulley over which a pair of cords pass in side-by-side relation; the cord-engaging surface of the pulley having coarse transverse corrugations; and a pivotally movable rubber locking dog. movable by cord contact to wedge the pair of cords against said pulley and into the space between the apices of successive corrugations, the cord-contacting face of the dog being concave to urge the cords toward one another as the dog moves into cord-locking position.

2. A cord lock comprising: a pulley over which a pair of cords pus in side-by-side relation, the cord-engaging surface of the pulley being concave and being provided with transverse corrugations; and a pivotally movable rubber locking dog movable by cord contact to wedge the pair of cords against said pulley and into the space between the apices ofsuccessivecorrugations, the cord-contacting surface of the dog being also concave.

SCO'I'I R. BOND. HANS K. LOREN'IZEN. 

